Sealer for slate tile

It is a "wet look" sealer that supposedly provides 20 year performance. My wife and I definately want to enhance the look of the slate and provide a good seal as well. I have been told that two coats are suggested. It is $85/quart. I anticipate needing at least three quarts.

I have a hunch that I'm paying a lot of markup?

Does anyone have experience with any other brand of slate/stone sealer that might be available online? $85/quart feels like a rip-off...Maybe it isn't?

Yep, I only use StoneTech when it's my decision. I just used a grout sealer from Tile Shop (not the one you linked to) that I wasn't so thrilled with. The HO bought the tile and grout herself and Tile Shop sold her this stuff as a recommendation. I personally thought it was not so good. But then again, that was a GROUT sealer, not a stone sealer.
YAWZ. Is that tile shop stuff really $85 per quart????? Yeah, don't bother with that.
For your case check this out:
Before grouthttp://www2.dupont.com/Stone_Tech_Pr...ct/sealer.html
After grouthttp://www2.dupont.com/Stone_Tech_Pr.../enhancer.html

It may not give you a high gloss finish (there are other products for that) but as far as I can tell, it would do the same as that tile shop stuff.